why does the world have global warming (full explabation)?

Answer 1

For over the past 200 years, the burning of fossil fuels, such as coal and oil, and deforestation have caused the concentrations of heat-trapping "greenhouse gases" to increase significantly in our atmosphere. These gases prevent heat from escaping to space, somewhat like the glass panels of a greenhouse.

Greenhouse gases are necessary to life as we know it, because they keep the planet's surface warmer than it otherwise would be. But, as the concentrations of these gases continue to increase in the atmosphere, the Earth's temperature is climbing above past levels. According to NOAA and NASA data, the Earth's average surface temperature has increased by about 1.2 to 1.4ºF since 1900. The warmest global average temperatures on record have all occurred within the past 15 years, with the warmest two years being 1998 and 2005. Most of the warming in recent decades is likely the result of human activities. Other aspects of the climate are also changing such as rainfall patterns, snow and ice cover, and sea level.

If greenhouse gases continue to increase, climate models predict that the average temperature at the Earth's surface could increase from 2.5 to 10.4ºF above 1990 levels by the end of this century. Scientists are certain that human activities are changing the composition of the atmosphere, and that increasing the concentration of greenhouse gases will change the planet's climate. But they are not sure by how much it will change, at what rate it will change, or what the exact effects will be.

In the U.S., our energy-related activities account for three-quarters of our human-generated greenhouse gas emissions, mostly in the form of carbon dioxide emissions from burning fossil fuels. More than half the energy-related emissions come from large stationary sources such as power plants, while about a third comes from transportation. Industrial processes (such as the production of cement, steel, and aluminum), agriculture, forestry, other land use, and waste management are also important sources of greenhouse gas emissions in the United States.

For a better understanding of where greenhouse gas emissions come from, governments at the federal, state and local levels prepare emissions inventories, which track emissions from various parts of the economy such as transportation, electricity production, industry, agriculture, forestry, and other sectors. EPA publishes the official national inventory of US greenhouse gas emissions, and the latest greenhouse gas inventory shows that in 2004 the U.S. emitted over 7 billon metric tons of greenhouse gases (a million metric tons of CO2 equivalents (MMTCO2e) is roughly equal to the annual GHG emissions of an average U.S. power plant.)

Climate change affects people, plants, and animals. Scientists are working to better understand future climate change and how the effects will vary by region and over time.

Scientists have observed that some changes are already occurring. Observed effects include sea level rise, shrinking glaciers, changes in the range and distribution of plants and animals, trees blooming earlier, lengthening of growing seasons, ice on rivers and lakes freezing later and breaking up earlier, and thawing of permafrost. Another key issue being studied is how societies and the Earth's environment will adapt to or cope with climate change.

In the United States, scientists believe that most areas will to continue to warm, although some will likely warm more than others. It remains very difficult to predict which parts of the country will become wetter or drier, but scientists generally expect increased precipitation and evaporation, and drier soil in the middle parts of the country. Northern regions such as Alaska are expected to experience the most warming. In fact, Alaska has been experiencing significant changes in climate in recent years that may be at least partly related to human caused global climate change.

Human health can be affected directly and indirectly by climate change in part through extreme periods of heat and cold, storms, and climate-sensitive diseases such as malaria, and smog episodes.

Greenhouse gases are emitted as a result of the energy we use by driving and using electricity and through other activities that support our quality of life like growing food and raising livestock. Greenhouse gas emissions can be minimized through simple measures like changing light bulbs in your home and properly inflating your tires to improve your car's fuel economy. The What You Can Do section of the climate change site identifies 30 action steps that individuals can take to decrease greenhouse gas emissions, increase the nation's energy independence and also save money.

State and local governments and businesses play an important role in meeting the national goal of reducing greenhouse gas intensity by 18 percent by 2012. For example, major corporations, states and local organizations are taking action through participation in a wide range of EPA and other federal voluntary programs.

You can start by assessing your own contribution to the problem, by using EPA's personal greenhouse gas emissions calculator to estimate your household's annual emissions. Once you know about how much you emit, you use the tool to see how simple steps you take at home, at the office, on the road, and at school can reduce your emissions.

Answer 2

Very thorough explanation of the possible effects of global warming, but not much of the causes found in the answers so far.

First and foremost, I always start a conversation with global warming by saying global warming is not bad. Life on Earth does not exist if the phenomena known as global warming does not exist. In fact, the Earth would still be a huge block of ice without global warming.

Another kind of ironic point is that water vapor is actually one of the most potent greenhouse gases; I'm not sure exactly how it compares to CO2, but i know they are similar. So the very thing that is necessary for life is part of the greenhouse effect. I suppose i say this because I'm personally against the negative reporting global warming gets-what it should be called is an artificially enhanced greenhouse effect or something to that nature.

Anyway, here's an explanation of how this actually works. Virtually all the energy which comes from the sun reaches the Earth's surface without any interference from the intermediate atmosphere. This energy is absorbed by the Earth's surface and in turn emitted. When this is emitted radiation tries to leave the Earth's atmosphere is when greenhouse gasses start to have an effect.

Water vapor and CO2 are the two most talked about greenhouse gases, so I'll use them. These molecules will absorb and re-emit the energy released by the Earth's surface, which as stated before is trying to escape the Earth. The problem is, when these gases absorb radiation that is trying to leave the Earth, it doesn't necessarily re-emit it in that same direction; some of it gets released back towards the Earth. This is the mechanism by which global warming occurs. Energy balance is very important to the Earth system, and greenhouse gases alter the equilibrium.

Answer 3

We have had freezing in Central CA a number of days for the last month or so. The nights when it does not freeze there is a cloud cover. The clouds seem to keep it warmer. That fits with the above discussion. But the thing that is never mentioned is the amount of CO2 produced by Jet engines in the high levels of the atmosphere. These jet engines burn 2-5 tons of fuel(kerosene) per hour. There are thousands of hours of jet traffic per day in the world. For each ton of fuel burned there is 3.66 tons of CO2 produced. Nature does not have a good mechanism of clearing that CO2. CO2 is heavier than air by about 50%, so I presume that it will slowly drift down to earth. At the surface, nature has created an unlimited need for CO2 by the plants. It is their basic food building block. The growing plants take it up instantly. Also the oceans are a giant buffer sink for CO2, as well as the sea plants using it. Since 85% of the earth is covered by water, the land plants are a very small user group when looked at in its entirety. The rise in CO2 as related by Mr Gore, has been occurring over the last 40 -50 years. This does match the use of the jet engine in high altitude flying. Green house experiments of adding CO2 to its atmosphere were unsuccessful in keeping the levels up. The plants took it up so fast, and grew faster and more lush.

Answer 4

Accumulation of green house gas in our atmospher via release of carbons traped in fossil fuels under ground.

Answer 5

dam man..... you took the book out of my mouth! LOL well i think he explained it all really ALL of it

Answer 6

lol. the first guy had my sanwer